Group Behavior

Learning Objectives

  • Illustrate when the presence of others is likely to result in groupthink, social facilitation, or social loafing


When in group settings, we are often influenced by the thoughts, feelings, and behaviors of people around us. Whether it is due to normative or informational social influence, groups have the power to influence individuals. Another phenomenon of group conformity is groupthink. Groupthink is the modification of the opinions of members of a group to align with what they believe is the group consensus (Janis, 1972). In group situations, the group often takes action that individuals would not perform outside the group setting because groups make more extreme decisions than individuals do. Moreover, groupthink can hinder opposing trains of thought. This elimination of diverse opinions contributes to a faulty decision by the group.

Dig Deeper: Groupthink in the U.S. Government

There have been several instances of groupthink in the U.S. government. One example occurred when the United States led a small coalition of nations to invade Iraq in March 2003. This invasion occurred because a small group of advisors and former President George W. Bush were convinced that Iraq represented a significant terrorism threat with a large stockpile of weapons of mass destruction at its disposal. Although some of these individuals may have had some doubts about the credibility of the information available to them at the time, in the end, the group arrived at a consensus that Iraq had weapons of mass destruction and represented a significant threat to national security. It later came to light that Iraq did not have weapons of mass destruction, but not until the invasion was well underway. As a result, 6000 American soldiers were killed and many more civilians died. How did the Bush administration arrive at its conclusions? Here is a video of Colin Powell discussing the information he had, 16 years after his famous United Nations speech, in which he spoke about how Iraq most certainly had materials to create weapons of mass destruction (“Colin Powell Says UN Presentation on Iraq ‘Fell on Me’,” 2017). Do you see evidence of groupthink?

Why does groupthink occur? There are several causes of groupthink, which makes it preventable. When the group is highly cohesive or has a strong sense of connection, maintaining group harmony may become more important to the group than making sound decisions. If the group leader is directive and makes his opinions known, this may discourage group members from disagreeing with the leader. If the group is isolated from hearing alternative or new viewpoints, groupthink may be more likely. How do you know when groupthink is occurring?

There are several symptoms of groupthink including the following:

  • perceiving the group as invulnerable or invincible—confidence in the strength of the group
  • believing the group is morally correct—believing it can do no wrong
  • self-censorship by group members, such as withholding information to avoid disrupting the group consensus
  • the quashing of dissenting group members’ opinions
  • the shielding of the group leader from dissenting views
  • perceiving an illusion of unanimity among group members
  • holding stereotypes or negative attitudes toward the out-group or others’ with differing viewpoints (Janis, 1972)

Given the causes and symptoms of groupthink, how can it be avoided? Several strategies can improve group decision making including seeking outside opinions, voting in private, having the leader withhold position statements until all group members have voiced their views, conducting research on all viewpoints, weighing the costs and benefits of all options, and developing a contingency plan (Janis, 1972; Mitchell & Eckstein, 2009).

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Group Polarization

Another phenomenon that occurs within group settings is group polarization. Group polarization (Teger & Pruitt, 1967) is the strengthening of an original group attitude after the discussion of views within a group. That is, if a group initially favors a viewpoint, after discussion the group consensus is likely a stronger endorsement of the viewpoint. Conversely, if the group was initially opposed to a viewpoint, group discussion would likely lead to stronger opposition. Group polarization explains many actions taken by groups that would not be undertaken by individuals. Group polarization can be observed at political conventions, when platforms of the party are supported by individuals who, when not in a group, would decline to support them. Recently, some theorists have argued that group polarization may be partly responsible for the extreme political partisanship that seems ubiquitous in modern society. Given that people can self-select media outlets that are most consistent with their own political views, they are less likely to encounter opposing viewpoints. Over time, this leads to a strengthening of their own perspective and of hostile attitudes and behaviors towards those with different political ideals. Remarkably, political polarization leads to open levels of discrimination that are on par with, or perhaps exceed, racial discrimination (Iyengar & Westwood, 2015). A more everyday example is a group’s discussion of how attractive someone is. Does your opinion change if you find someone attractive, but your friends do not agree? If your friends vociferously agree, might you then find this person even more attractive?

Social traps refer to situations that arise when individuals or groups of individuals behave in ways that are not in their best interest and that may have negative, long-term consequences. However, once established, a social trap is very difficult to escape. For example, following World War II, the United States and the former Soviet Union engaged in a nuclear arms race. While the presence of nuclear weapons is not in either party’s best interest, once the arms race began, each country felt the need to continue producing nuclear weapons to protect itself from the other.

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Social Loafing

Imagine you were just assigned a group project with other students whom you barely know. Everyone in your group will get the same grade. Are you the type who will do most of the work, even though the final grade will be shared? Or are you more likely to do less work because you know others will pick up the slack? Social loafing involves a reduction in individual output on tasks where contributions are pooled. Because each individual’s efforts are not evaluated, individuals can become less motivated to perform well. Karau and Williams (1993) and Simms and Nichols (2014) reviewed the research on social loafing and discerned when it was least likely to happen. The researchers noted that social loafing could be alleviated if, among other situations, individuals knew their work would be assessed by a manager (in a workplace setting) or instructor (in a classroom setting), or if a manager or instructor required group members to complete self-evaluations.

The likelihood of social loafing in student work groups increases as the size of the group increases (Shepperd & Taylor, 1999). According to Kamau and Williams (1993), college students were the population most likely to engage in social loafing. Their study also found that women and participants from collectivistic cultures were less likely to engage in social loafing, explaining that their group orientation may account for this.

College students could work around social loafing or “free-riding” by suggesting to their professors use of a flocking method to form groups. Harding (2018) compared groups of students who had self-selected into groups for class to those who had been formed by flocking, which involves assigning students to groups who have similar schedules and motivations. Not only did she find that students reported less “free riding,” but that they also did better in the group assignments compared to those whose groups were self-selected.

Interestingly, the opposite of social loafing occurs when the task is complex and difficult (Bond & Titus, 1983; Geen, 1989). In a group setting, such as the student work group, if your individual performance cannot be evaluated, there is less pressure for you to do well, and thus less anxiety or physiological arousal (Latané, Williams, & Harkens, 1979). This puts you in a relaxed state in which you can perform your best, if you choose (Zajonc, 1965). If the task is a difficult one, many people feel motivated and believe that their group needs their input to do well on a challenging project (Jackson & Williams, 1985).


Another way that being part of a group can affect behavior is exhibited in instances in which deindividuation occurs. Deindividuation refers to situations in which a person may feel a sense of anonymity and therefore a reduction in accountability and sense of self when among others. Deindividuation is often pointed to in cases in which mob or riot-like behaviors occur (Zimbardo, 1969), but research on the subject and the role that deindividuation plays in such behaviors has resulted in inconsistent results (as discussed in Granström, Guvå, Hylander, & Rosander, 2009).

Watch It

Consider examples of social influence and groupthink and review the concepts you learned previously about conformity and obedience in the following CrashCourse video:

You can view the transcript for “Social Influence: Crash Course Psychology #38” here (opens in new window).

The table below summarizes the types of social influence.

Table 1. Types of Social Influence
Type of Social Influence Description
Conformity Changing your behavior to go along with the group even if you do not agree with the group
Compliance Going along with a request or demand
Normative social influence Conformity to a group norm to fit in, feel good, and be accepted by the group
Informational social influence Conformity to a group norm prompted by the belief that the group is competent and has the correct information
Obedience Changing your behavior to please an authority figure or to avoid aversive consequences
Groupthink Tendency to prioritize group cohesion over critical thinking that might lead to poor decision making; more likely to occur when there is perceived unanimity among the group
Group polarization Strengthening of the original group attitude after discussing views within a group
Social facilitation Improved performance when an audience is watching an individual perform a skill they excel at versus when the individual performs the behavior alone
Social loafing Exertion of less effort by a person working in a group because individual performance cannot be evaluated separately from the group, thus causing performance decline on easy tasks

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group polarization: strengthening of the original group attitude after discussing views within the group
groupthink: group members modify their opinions to match what they believe is the group consensus
informational social influence: conformity to a group norm prompted by the belief that the group is competent and has the correct information
normative social influence: conformity to a group norm to fit in, feel good, and be accepted by the group
obedience: change of behavior to please an authority figure or to avoid aversive consequences
social facilitation: improved performance when an audience is watching versus when the individual performs the behavior alone
social loafing: exertion of less effort by a person working in a group because individual performance cannot be evaluated separately from the group, thus causing performance decline on easy tasks